Silo-scaffold.



oLor r. JOHNSON, or GRANITE FALLS, MINNESOTA.

SILO-SCAFFOLD.

Specification of Letters Patent.

Patented Nov. 12, 1918.

Application filed September 2, 1915, Serial NO. 48,639. Renewed February 26, 1918. Serial No. 219,339.

To all whom it may concern:

Be it known that I, OLOF F. JoHNsoN, a citizen .of the United States, residing at Granite Falls, in the county of Kandiyohi and State of Minnesota, have invented certain new and useful Improvements in Silo- Scaffolds, of which the following is a specification. v v 1 My invention relates to raisable silo scaffolds and has for its object to provide a silo i scaffold which can readily and quickly. be raised as the silo is being built, and which is neither cumbersome nor complex.

The full objects and advantages of my invention will appear in connection with the detailed description thereof and are pa-rticularly pointed out in the claims.

In the drawings, illustrating the application of my invention in one form, I Figure 1 is a plan view of a partially constructed' silo showing my improved scadold and raising device, said scaffold being raised and in place with some parts removed to show Others beneath them. Fig. 2 is an elevational sectional view on line 22 of Fig.

1 of the parts shown in Fig. 1. Fig. 3 is a.

plan view of a portion of the parts shown in Fig. 1 with the scaffold supports withdrawn from the wall of the silo and the said scaffold in a position to be raised. Figs. 4 and 5 are elevational sections of the scaffold platform taken on lines H and 55 of Fig. 3, respectively. Figs. 6 and 7 are elevational sections of the scaffold platform supports taken on lines 6-6 and 77 of Fig. 1, respectively. Fig. 8 is a plan view and Fig. 9 a sectional view on line 99 of.

Fig. 8 ofanother form of scaffold especially adapted. to large silos. Figs. 10, 11, 12 and 13 are sectional elevational views taken on lines 10-10, 11-11, 1212 and 1313, respectively of Fig. 8.

My invention is well adapted to silo construction of the concrete block type. Such a silo is shown in the drawings. Blocks 10 of the usualform, rectangular in shape, having fiat horizontal edges and curved vertical edges are laid in courses one on theotherf so as to break horizontal joints, and are held together by means of their curved edges and l circumferential bands 11. These blocks arehoisted up to an internal scaffold where they are held in place in the usual manner.

A plurality of segmental platforms 12 are to rest. The positions of the 13, which through extensions 15 and supporting plates 16 rest on the tops of the blocks 10 and are pivotally connected at the points 31 to the under side of an annular supporting frame 14. Arms 13are tubular and are. adjustable in length through the extens1ons'15 which slide within them and may be fastened to them. Extensions 15 carry the supporting plates 16, which rest on the tops of the blocks 10.

The raising device used in connection with my scaffold is shown in Figs. 1 and 2. It consists of a pair of planks 17 and 18 provided with hearing blocks 19, as best shown in Fig. 1. Two pipes 20 and 21 rotate in these blocks 19 and are provided with hand cranks 22 for securing this rotation. Pipes 20 and 21 have also secured to them ropes 23, 24:, 25 and 26, which are attached to the extension arms 15 and are adapted to wind upon said pipes when the same are rotated to cause the whole scafiold to be raised. The planks are laid on the tops of blocks 27. of the upper course, and the supports 16 are raised to thetops of blocks 28 of the next lower alternate course, where they are caused parts in raising are shown in Fig. 3, and the attachment of the raising device is shown in Figs. 1

' and 2.

' The methodof withdrawing and ejecting the'arms 13 and plates 16 from the silo wall is best shown in Figs. 1, 2 and 3. A ring 29 is fastened by braces 30 to the annular supporting frame member 14 and serves to stiffen the whole scaffold and reduces the tendency of the arms 13.to break away at their pivots 31. Ring 29 is provided with an eyelet 32 to which is attached a rope 33. By means of this rope, ring 29 and frame member 14 are revolved about a quarter of a turn and arms 13 may hence be ejected or withdrawn, as the pivots situated on frame member 14 serve as cranks and make this movement possible. When arms 13 and 15 are projected. any irregular formation of the wall of the silo is immediately corrected and the surface is thus maintained a perfect cyl inder. After the plates 16 are in place the blocks 10 are placed in their respective positions on top of said plate, and when the required number of rounds has been completed the plates 16 are withdrawn and the blocks on top of them drop down in their correct positions.

The platform members 12 are loosely placed upon putlogs 34 and 35 which are bent at their ends to hook over ledger members 36, 37, 38 and 39 as best shown in Figs. 4 and 5. Members 36 and 37 are preferably made of angle iron and are bolted together. Members 38 and 39 are made of bar iron and are bolted together in the form of a circle and are secured to members 36 and 37 by means of U-straps 40 as best shown in Figs. 1, 6 and 7. Short angle bars 41 attached to the ends of the extension arms 15 pass in the openings between the ledger members and 37, or 38 and 36 and the U-straps 40, and so support platforms 12 upon the arms 13 of the scaffold. As is clearly seen in. Figs. 1 and 3, the ledger members are short enough so that the platforms may be withdrawn from the inner surface of the silo wall to let the supporting plates 16 be withdrawn from said wall and the whole scaffold raised.

To make this scaffold adaptable to various sizes of silos members 3839, 36-37 and 13-15 are secured together and may be adjusted to secure various lengths and hence fit various silos. lVhen the number of blocks in a circumference is such that all of the plates 16 cannot rest upon a block :28, one or more of said plates 16 may be attached to the U-straps 40, shown at 43. Different sizes of platform planks 12 must, however, be provided.

The hoist used. in raising the blocks 10 and other building material of the ordinary form and is attached to a tripod formed of legs 42 attached to the ring 29, but is not shown in the drawings.

In conjunction with very large silos the platform members 1:? become so wide that the scaffold becomes clumsy and inconvenient to handle. In such cases I employ an extra set of projected members and double the number of platform members. as clearly shown in Figs. 8 to 13.

A slightly modified form of projecting devic is shown in Figs. 8 and 9. A pair of U-shaped crossbars 45 are placed at right angles to each other and attached with the stems down to a ring 46. Similar bars 47 are placed at an angle of forty-five degrees with bars 45 and are attached to the ring 46 with their stems up. At suitable distances from the ring 46 are pivotally attached to the lower sides of bars 47 four extensible arms 48 supplied with supporting plates 49 identical with the other form of construction, which arms support the scaffold on the wall in an identical manner. From the farthermost edge of each of the arms 48 extend four brace members 50 attached to each.

- other and supported upon the arms 48 by connecting bands 51, as best shown in Fig.

10. These bands are provided at their ends close the ends of the braces 50 and to receive a nut 53 and bolt 54 by means of whichsaid braces can be easily and rigidly secured thereto. Bands 51 are further looped at 55 to fit arms 48, bringing the level of the braces 50 even with the bottom of said arms, and yet allowing the arms to be receded from the wall by sliding within said loops.

Secured to the top of crossbars 45 in similar manner to arms 48 are a like number of arms 56 which rest upon the braces 50, as shown in Fig. 8. These arms do not carry the supporting plates 49 but merely serve in conjunction with arms 48 to support plat form members 57. As best shown in Fig. 11, each platform member 57 comprises a single plank, to which is bolted at one end a bar 58 having a downwardly-pro}ecting bend 59, and at the other end a similar bar 61 having-an upwardly-projecting bend 60. These bars rest one upon the other and upon the arms 48 and 56 in a manner indicated in said Fig. 11 and so support the platform members 57. Clamps 62 and 63 are pivotally attached to the ends of arms 56 and 48, respectively, as shown in Figs. 13 and 12, and are provided with recesses 64 for the reception of bars 58 and 61 and with spring clips 65 engageable with rings 66. Thus a simple device is formed whereby the bars 58 and 61 may quickly be secured, said device allowing the bars to slide longitudinally relatively to each other as the circumference of the silo is contracted without becoming disengaged from each other.

The arms 48 and 56 are receded in a manner similar to the first described form, of scaffold by means of a piece of timber 67 placeable in U-shaped slots 68 formed in a pair of parallel bars 69 attached to ring 46.

The manipulation of this form of scaffold is identical with that previously described and mention of the tripod and raising means is unnecessary. This latter form is to be preferred over the former in that it is simpler and adaptable to larger sizes of silos. The main features are, however, identical and the principles involved the same. With either form much time is saved in erecting and using the scafiold, and the same can be easily dismantled and transported from one place to another in an automobile, avoiding delays caused by railway transportation.

I claim:

1. A scaffolding for circular silos comprising a plurality of supports each formed with an outer portion extending in an arc of a circle, said supports taken conjointlv forming a circular scaflolding, means for. connecting said supports, means attachedto said connecting means for holding the supports suspended from the silo wall, and means for moving the supports radially toward and from the silo wall.

2. A scaffolding for circular silos comprising a plurality of supports each formed with an outer portion extending in an arc of a circle, said supports taken conjointly forming a circular scaffolding, means for connecting said supports, means attached to said connecting means for holding the supports suspended from the silo wall, rods attached to said suspending means, and means for moving all of said rods radially to move said supports away from and toward the silo wall.

3. A scaffolding for circular silos comprising a plurality of supports each formed with an outer portion extending in an arc of a circle, said supports taken conjointly forming a circular scaifolding, means for connecting said supports, means attached to said connecting means for holding the supports suspended from the silo wall, a rotatable center body, rods attached to the suspending means and said body, means for rotating the center body and thereby mov ing the suspending means and the supports connected thereby radially away from and toward the silo Wall.

l. A scaffolding for circular cement stave silos comprising a substantially circular scaffolding within the silo, means for sup porting the scaifolding from the silo wall comprising a plurality of radially movable lugs adapted to engage over said silo wall and for connection with the scaffolding, and means for moving said lugs radially.

5. A scaffolding for circular silos comprising a central member and two sets of rods radiating therefrom, the rods of said respective sets alternating, means attached to each rod of one of said series for en gaging over the edge of the silo wall to support the scafi'olding, frame pieces adjustably secured to the rods of said lastnamed series, and operating to support the rods of the other series, and a, plurality of supports connected so as to be capable of approaching and receding from one another to and between adjacent pairs of rods of the two series.

6. A scaffolding for circular silos comprising a central member and two sets of rods radiating therefrom, the rods of said respective sets alternating, means attached to each rod'of one of said series for engaging over the edge of the silo wall to support the scaffolding, frame pieces adjustably secured to the rods of said last-named series, and operating to support the rods of the other series, and a plurality of supports connected so as to be capable of approaching and receding from one another to and between adjacent pairs of rods of the two series, all of the rods of both sets being pivotally connected with said central member at points offset from the center thereof so that rotation of the central member will sinliultaneously project or retract all of said roc s.

7 A scaffolding for circular silos com prising a central member and four radial members connected with said central member and extending in oppositely-disposed pairs substantially at right angles one pair with the other, a substantially rectangular frame supported at its corners upon said radial members, means connected with the radial members for engaging over the wall of the silo to support the scaffolding, a plurality of arms intermediate said radial members extending to a point adjacent the scaffolding wall and supported by said rectangular frame, and a series of scaflold supports carried by said radial members and arms.

In testimony whereof I aflix my signature in presence of two witnesses.

OLOF F. JOHNSON. lVitnesses F. A. W'HITELEY, H. A. BOWMAN.

Copies of this patent may be obtained for five cents each, by addressing the "Commissioner of Patents,

Washington, D. C. 

